• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Adaptation and Natural selection

Extracts from this document...

Introduction

International Baccalaureate Nattapat Khongchumchuen Biology Adaptation and Natural selection Introduction Adaptation that is, the way that species' anatomy, physiology, and behaviour appear to be well suited to the demands of their environments. Adaptation is pervasive in nature. Moreover, once created, species were believed to change little, through time. In his Origin of Species, published in November 1859, Darwin explained the purpose of the book as follows: "I had two distinct objects in view; firstly to show that species had not been separately created, and secondly, that natural selection had been the chief agent of change." Natural selection, Darwin believed, explained how species became adapted to their environments. Natural selection, then, is differential reproductive success, with heritable favourable traits bestowing a survival advantage on those individuals that possess them. Generation by generation, favourable traits will become ever more common in the population, causing a micro-evolutionary which shift within the species. Such traits will remain favoured, however, only if prevailing conditions remain the same. A species' environment usually does not remain constant in nature. A change in a species' physical or biological environment may alter a population's adaptive landscape, making a less advantageous trait more favourable. ...read more.

Middle

Also, the local area differences of the snails may affect the snails' colours. The low frequency of bright colours on the snail's shell in K�pavogur is likely to be due to the relative absorption of solar energy of snails' shell because they mostly live under seaweed and in �lftanes, the snail's shell will be darker in colour due to sunlight absorption. The snails in �lftanes shore do not live under seaweed, so sunlight absorption will be less, this due to the environmental selection in area effects. Design: Controlled variable: two identical plastic cups, random sampling using same method and 17 Snails on each shore Independent variable: K�pavogur shore and �lftanes shore Dependent variable: Colours of snails Data collection: Materials 1) Two plastic cups 2) One pair of latex gloves Method 1) Name two cups which will be used to collect the snails on K�pavogur and �lftanes shores. 2) Pick the snails randomly around the area (use latex gloves) with approximately 10 steps forward from the shore (starting point), 5 steps on the right and finally 5 steps on the left. 3) Redo 2) one more time 4) Collect approximately 17 snails 5) Kill the snails by pouring ethanol into both cups and let the snails die, wait for the next day 6) ...read more.

Conclusion

Also, when snails live on the shore, environment affects their living condition such as those snails that live under seaweed would not absorb sunlight properly, so they have darker colour that the one that absorb sunlight properly. My hypothesis proves to be true due to environmental effect and sexual reproduction. We could measure the sizes of the snails and do the T-test if we measure the size of the snails, in this case we could not be able to do that. As the colours are investigated T-test cannot be carried out. Colours have limited on the quality of the data because it cannot be measure probably, instead of measuring the sizes we calculate percentage of the snails on each shores. In design the dependent variable should be the sizes because we could observe the differences in natural selection though sizes rather than colour. When colours are investigated it has lack accuracy to observe the changes in natural selection and adaptation. To improve the investigation we have to clean the snails more than two times to see whether the colours have changed or not. Do not use ethanol to kill them because it could affect on the colours of the snails� shell and it may become white because the use of the chemical. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our International Baccalaureate Biology section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related International Baccalaureate Biology essays

  1. Experiment Colours of Light (Wavelength) absorbed by green plant

    One is near to the wavelength value of 425 nm and another one is near to 650 nm. Another peak is also formed at the through of the graph which is at 540 nm. These two peaks indicate that there is a very high absorption of wavelength.

  2. The effect on osmosis on the egg shell

    "height" of solution varied, this affected degree of submergence Weaknesses (note that more significant weaknesses will be indicated with "s")

  1. Lion King-The Ecological study

    This is somewhat alike to detritivores which stands last in the food chain/web which recycle all the energy in the nutrients that stay inside the bodies of the dead 10. They recycle as much as they can the carbon-based nutrients in Simba.

  2. Ecology Open Investigation Does the geographic location affect the biotic and abiotic ...

    Rating Categories Sensitivity Score Taxa Richness S > 4.5 3.5 < S < 4.5 S < 3.5 x > 9 Good Moderate Moderate 3 < x < 9 Moderate Moderate Poor x < 3 Moderate Poor Poor Note: - Good - Many taxa (high diversity), sensitive taxa present.

  1. Human variation

    It can also be performed without the need of assistance from others. However, there are certain factors that had an impact on the results obtained. One factor is the age of the students. All of the students were teenagers of age 16.

  2. Should Animals have the same rights as Humans? Both animals and humans exhibit behaviours ...

    Many new parents experience the problem of babies waking repeatedly in the night and not going back to sleep until they are cuddled or rocked. It is not only normal but essential for humans to wake several times in the night to readjust the position of their body to avoid injury by lying in one position for too long.

  1. Biology- Extended essay. For this research, I investigated the effects of DDT and ...

    In my experiments DDT will be added to the fish's environment and there direct response would be shown by the difference in their opercular movement. THE TEXTILE INDUSTRY:- The textile printing in Sanganer town, district Jaipur (Rajasthan, India), is famous worldwide for its dyeing and printing industries.

  2. Comparing the Sexy Sons Hypothesis and the Pathogen Avoidance Models Effects on Sexual Selection

    These ornamental traits are known to negatively affect the longevity of the individual but benefits its reproductive success. Essentially, females prefer to choose attractive and showier mates in order to produce attractive sons who are selected for by females, which leads to greater amount of grandchildren and so on.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work